Due to popularization of environmental protection education and continuous warnings on overburden of the earth environment according to the natural sciences, in modern societies, people in the advanced countries have strong awareness in environmental protection and energy preservation. Countries worldwide seek for renewable energies to replace thermal and nuclear power generation. Consequently, wind, solar, geothermal, and tidal power generation technologies have been developing and improving constantly.
While developing renewable energies, governments worldwide promote energy and carbon reduction aggressively. Take household power consumption for example. According to the statistics of the US in 2008, household power consumption occupies 37% of the total power consumption. Besides, most people have improper habits of power consumption but are not aware of it, resulting in waste in the electric energy. Accordingly, once people's habits of domestic power consumption can be investigated, the purpose of energy preservation and carbon reduction can be achieved effectively.
Nonetheless, the meters used by most current electric power consumers are traditional meters, which can only provide the total power consumption of the electric power consumer in the past month or in the past period. Then, by comparing the total power consumption with that in the previous month or in the same period of the last year, whether the power consumption of the electric power consumer is improved can be observed.
There have many advanced countries that adopt novel smart meters and weed out traditional ones. Although smart meters can give the current power consumption of an electric power consumer real-timely, it is difficult for them to identify the operation conditions of the electric power consumer's appliances for further analysis on the power consumption behavior of the electric power consumer and accordingly planning and managing energy preservation.
To analyze the power consumption behavior of an electric power consumer, most current methods are invasive load operation detection. For applying the detection method, an extra measuring apparatus or sensing device should be installed to each load (namely, each appliance) of the electric power consumer. According to the information given by the measuring apparatus or sensing device, whether the individual load is in the on or off condition can be judged. Although this method can acquire the load operation conditions of an electric power consumer, the adoption cost is expensive and the maintenance is challenging, making it difficult to promote to all electric power consumers. Consequently, the invasive method for acquiring the load operation conditions of an electric power consumer is not popular.
Accordingly, it is required to have a method for noninvasively acquiring the load operation conditions of an electric power consumer.